skill-management

name	skill-management
description	Install, uninstall, and list agent skills. Handles NTFS hardlinks for auto-sync with source repos.

Skill Management

This skill handles installing, uninstalling, and listing agent skills.

Skills live at: C:\Users\galaxywin\.gemini\antigravity\skills\

Each skill is a folder containing a SKILL.md file with YAML frontmatter (name, description).

Installing a Skill

When the user says "install skill" and provides a path (to a SKILL.md or a directory containing one):

1. Resolve the path. If a directory, look for SKILL.md inside it.
2. Read the frontmatter to get the name field — this becomes the folder name.
3. Check for conflicts. If skills/<name>/ exists, ask before overwriting.
4. Create the skill folder:

   New-Item -ItemType Directory "C:\Users\galaxywin\.gemini\antigravity\skills\<name>" -Force
   

5. Create an NTFS hardlink for auto-sync:

   cmd /c mklink /H "C:\Users\galaxywin\.gemini\antigravity\skills\<name>\SKILL.md" "<source>\SKILL.md"
   

6. Verify:

   $links = (fsutil hardlink list "C:\Users\galaxywin\.gemini\antigravity\skills\<name>\SKILL.md").Count
   if ($links -gt 1) { "✅ Installed and synced" } else { "❌ Failed" }
   

Why hardlinks?

• Auto-synced — same file on disk, edits to source are instant.
• No admin required — unlike symlinks on Windows.
• Clean — only SKILL.md appears, not the entire repo (unlike directory junctions).

Rules

• NEVER use .lnk shortcuts — invisible to the skill scanner.
• NEVER use directory junctions to repos — leaks node_modules/src/dist and breaks the scanner.
• NEVER just copy without hardlinking — goes out of sync.
• If source and target are on different drives, hardlinks won't work. Copy instead and warn the user.

Uninstalling a Skill

Remove-Item "C:\Users\galaxywin\.gemini\antigravity\skills\<name>" -Recurse -Force

Safe — only removes the hardlink. The original SKILL.md in the source repo is untouched.

Listing Skills

Get-ChildItem "C:\Users\galaxywin\.gemini\antigravity\skills" -Directory |
  ForEach-Object { $_.Name + " => " + (Select-String "^description:" "$($_.FullName)\SKILL.md").Line }

Skill Update Protocol

When you learn something new that should be remembered across conversations, update the relevant skill's SKILL.md immediately. Examples:

• User corrects a mistake → add a rule to prevent it (e.g. "always commit before moving on" was added to git-workflow after forgetting)
• A new pattern or convention emerges → document it in the relevant skill
• A common error is encountered → add it to troubleshooting

When to update skills:

1. During the current task — if you discover something worth remembering, update the skill NOW, don't wait
2. When user explicitly says "remember this" — add to the most relevant skill
3. When a bug was caused by missing knowledge — add a rule to prevent recurrence

Never wait until "later" to update skills — that's how knowledge gets lost between conversations.